Tachometer Generators Applications

DC Tach Generators in Servo Systems

Combining high accuracy with low driving torque, Servo-Tek tach generators are ideal for use in servo systems. Tach Generators are particularly suited to application in precision integrators and velocity servos, both of which require a highly linear speed/voltage relationships with minimum ripple. DC Tachometer Generators are also excellent rate generators for velocity damping in position servos.

Speed Transducers/DC Tach Generator

The nearly pure dc output-with no phase shift-allows Servo-Tek Tach Generators to be used as feedback transducers for numerous types of equipment, including fast-response servos and other devices.

Tach Generator Construction

Servo-Tek Tach Generators are housed in aluminum casings protected in accordance with Mil-C-5541 or Mil-A-8625. Alnico permanent magnets are used. Armature shafts are stainless steel, and rotate on fully-shielded stainless steel ball bearings. Commutators are made from an alloy containing 95% silver. Armature laminations are wound with Isomid insulated wire, over Teflon slot insulation. The entire armature is impregnated and baked, resulting in a NEMA Class H insulation system.

Brush Life/DC Tachometers

Tachometer Generator brushes and commutators are matched for long life and stability. Operation at 1 mA output will deliver maximum brush life.

Linearity/DC Tachometers

Linearity, of Servo-Tek DC Tach Generators, at any speed is better than 0.1% of the output at that rpm.

Ripple/DC Tachometer

The DC Tachometer Generator ripple rms value will not exceed 3% of the dc value at any speed in excess of 40 rpm on standard units; 1.5% on low-ripple models.

Bidirectional Operation/DC Tachometers

All Servo-Tek DC Tach Generators operate in either rotational direction. That direction can be determined by output voltage polarity. Output (in either direction) is held to a tolerance of 0.25% of the average output.

Stability/DC Tachometers

Breakdown Voltage/DC Tachometers

Servo-Tek DC Tach Generators are factory tested with an ac potential of 1,250 volts rms applied for one second between (either) terminal and the shaft. Series E-500 volts.)

Temperature Range

Tachometer Generators are designed for continuous operation in ambient temperatures ranging from -55°C to +100°C(-67°F to +212°F). Voltage output at 25°C will not deviate by more than 0.01% per degree of change within the range of -20°C to +75°C. All Tachs are temperature compensated, with the exception of Series D and E.